The UW Clinical Research Core was initiated in 1988 to support pilot clinical trials proposed by UW junior faculty members of senior faculty initiating new research in the area of HIV. Since its inception it has supported 17 clinical trials enrolling over 900 patients. Over 20 publications have ensued from this work, and the pilot data have led to 8 funded research applications. In this funding period we propose to expand the UW CFAR to include both a Seattle based and Internationally based CRC. The Seattle based program will continue to emphasize short term limited support of interdisciplinary studies that are directed at the epidemiology and biology of HIV acquisition/transmission. One current effort is a detailed study of the immunologic and virologic aspects of acute subclinical primary HIV-1 infection. Within last few years, the UW has established several cohort studies in International sites that are directed at the transmission/acquisition of HIV infection. The International CRC will directed at improving the interdisciplinary aspects of these studies. CFAR International CRC resources will be devoted at supporting the acquisition, storage and shipment of specimens from these cohort studies of collaborating laboratory based investigators at the UW; especially those involved in retrovirology and immunology based research. To date, the request for CFAR CRC resources have far exceeded available resources. An Internal Scientific Review Committee consisting of the CFAR CRC resources have far exceeded available resources. An Internal Scientific Review Committee consisting of the CFAR Director, Associated Directors and the Internal Review Committee listed below will review concept sheets from CFAR investigators and prioritize the utilization and duration of CFAR resources for approval projects.